Different types of organisms vary in their response to antiseptics and disinfectants. The microbial susceptibility to antiseptics and disinfectants of various organisms has been summarized as shown in the following schematic. McDonnell, Gerald et al., “Antiseptics and Disinfectants: Activity, Action, and Resistance,” Clinical Microbiology Reviews, Vol. 12, pp. 147-179 (January 1999). Organisms are listed in descending order of resistance.                Prions (CJD, BSE)                Coccidia (Cryptosporidium)                Spores (Bacillus, C. difficile)                Mycobacteria (M. tuberculosis, M. avium)                Cysts (Giardia)                Small non-enveloped viruses (Polio virus)                Trophozoites (Acanthamoeba)                Gram-negative bacteria (non-sporulating) (Pseudomonas, Providencia)                Fungi (Candida, Aspergillus)                Large non-enveloped viruses (Enteroviruses, Adenovirus)                Gram-positive bacteria (S. aureus, Enterococcus)                Lipid enveloped viruses (HIV, HBV)        
Bacterial spores of the genera Bacillus and Clostridium have been widely studied and are considered to be the most resistant of all types of bacteria to antiseptics and disinfectants.
Clostridium species are significant pathogens. Infections among patients in healthcare facilities caused by the bacteria Clostridum difficile (C. difficile), are at historically high levels. C. difficile is a spore-forming, Gram-positive anaerobic bacillus of the human intestine and is thought to be present in 2-5% of the adult population. Pathogenic C. difficile strains produce multiple toxins, the most well-characterized of which are enterotoxin (Clostridium difficile toxin A) and cytotoxin (C. difficile toxin B), both of which can produce diarrhea and inflammation in infected patients. The emergence of a new, highly toxic strain of C. difficile, resistant to flouroquinolone antibiotics, such as ciprofloxacin and levofloxacin have also been reported. C. difficile infection causes diarrhea and other intestinal problems and is linked to 14,000 deaths in the United States each year.
Control of C. difficile outbreaks present significant challenges to health care facilities. C. difficile spores survive routine environmental cleaning with detergents and hand hygiene with alcohol-based gels. The spores can survive on surfaces for long periods of time. As a result, the bacteria can be cultured from almost any surface. Once spores are ingested, their acid-resistance allows them to pass through the stomach unscathed. They germinate and multiply into vegetative cells in the colon upon exposure to bile acids.
A variety of strategies have been proposed to kill C. difficile spores on various surfaces, with limited success. Bleach-based compositions have been employed for hard surfaces, and have been shown to reduce the environmental burden of C. difficile but can be corrosive. Hydrogen peroxide-based compositions have also been proposed, including combinations of hydrogen peroxide and peracetic acid, a combination of hydrogen peroxide and silver cation dry-mist system, and the so-called Accelerated Hydrogen Peroxide (AHP). Peracids generally have poor stability, odor and corrosive properties. Hydrogen peroxide is also prone to decomposition, and concentrated solutions can be highly corrosive. Alcohol-based sanitizers have not generally been effective. In fact, ethanol is sometimes used to store C. difficile spores.
A need remains for more stable, less corrosive compositions having good efficiency against C. difficile spores, as well as against other pathogenic infectious agents such as bacteria, fungi, viruses, fungal and bacterial spores, and conformationally altered prions, some of which can be particularly resistant to current sanitizers and cleansers.
Somewhat relatedly, there is growing concern about the use of biological toxins and infectious agents such as conformationally altered prions, bacteria, viruses, and fungal and bacterial spores, as biological and chemical warfare agents. Chemical and biological warfare agents can be fast-acting and pervasive. There is a continuing need for effective, easy to use products that will be safe for humans and the environment, that can be used to decontaminate skin, and particularly wounds, following chemical and/or biological warfare agent exposure. Furthermore, there is a need for effective products that can be used to decontaminate homes, building materials, and furniture that can decontaminate surfaces to eliminate these infectious agents, and that can reduce the transmission of the infectious pathogens.